Flow cytometric characterization of the hemocytes of blood cockles Anadara broughtonii (Schrenck, 1867), Anadara kagoshimensis (Lischke, 1869), and Tegillarca granosa (Linnaeus, 1758) as a biomarker for coastal environmental monitoring.

Marine bivalves are often used as a sentinel species in coastal environmental monitoring since changes in the environmental quality are often well preserved in their cells and tissues. Anadara and Tegillarca species of Arcidae, the blood cockles, are considered to be good sentinel species in monitoring coastal pollution and ecosystem health because they are distributed widely in the subsurface of intertidal mudflats. Internal cellular defense of the blood cockles to physical and biological stresses is mediated by the circulating hemocytes, while their hemocyte types and functions are poorly studied. In this study, we first characterized morphology and immune-related activities of hemocytes of three common blood cockles Anadara broughtonii, A. kagoshimensis, and Tegillarca granosa using flow cytometry. Based on cell morphology and immunological functions, we described five types of hemocytes identically in the three blood cockles: erythrocytes type-I (erythrocytes-I), erythrocytes type-II (erythrocytes-II), granulocytes, hyalinocytes, and blast-like cells. Erythrocytes were round cells containing hemoglobin with numerous granules in the cytoplasm and these cells consist of two central populations. Erythrocytes-I were the most abundant cells accounting for 80-89% of the total circulating hemocytes and exhibited a certain level of lysosome and oxidative capacity. Erythrocytes-II were the largest cells and displayed high lysosome content and the most active oxidative capacity. Both erythrocytes-I and erythrocytes-II did not show phagocytosis capacity. Granulocytes were intermediated-sized hemocytes characterized by granules in the cytoplasm and long pseudopodia on the cell surface, and these cells were mainly engaged in the cellular defense exhibiting the largest lysosome content, the most active phagocytosis, and high oxidative capacity. Contrary to granulocytes, hyalinocytes were comparatively small and round cells and exhibited no granules in the cytoplasm. Hyalinocytes displayed a certain level of lysosome and phagocytosis and oxidative capacities. Blast-like cells characterized by the smallest size and small quantity of cytoplasm and exhibited an absence of phagocytosis and extremely low oxidative capacity, suggesting that this population is not directly involved in the cell-mediated immune activities. In conclusion, flow cytometry indicated that three blood cockles had five types of hemocytes, and the erythrocytes and granulocytes were mainly involved in the immunological activities.

Biological Effects of the Herbal Plant-Derived Phytoestrogen Bavachin in Primary Rat Chondrocytes.

The aim of this study was to examine the anabolic and anticatabolic functions of bavachin in primary rat chondrocytes. With bavachin treatment, chondrocytes survived for 21 d without cell proliferation, and the proteoglycan content and extracellular matrix increased. Short-term monolayer culture of chondrocytes showed that gene induction of both aggrecan and collagen type II, major extracellular matrix components, was significantly upregulated by bavachin. The expression and activities of cartilage-degrading enzymes such as matrix metalloproteinases and a disintegrin and metalloproteinase with thrombospondin motifs were inhibited significantly by bavachin, while tissue inhibitors of metalloprotease were significantly upregulated. Bavachin inhibits the expression of inducible nitric oxide synthase, a representative catabolic factor, and downregulated the expression of nitric oxide, cyclooxygenase-2, and prostaglandin E2 in a dose-dependent manner in chondrocytes. Our results suggest that the bavachin has anabolic and potent anticatabolic biological effects on chondrocytes, which may have considerable promise in treating articular cartilage degeneration in the future.

Development of an Experimental Animal Model for Lower Back Pain by Percutaneous Injury-Induced Lumbar Facet Joint Osteoarthritis.

We report generation and characterization of pain-related behavior in a minimally invasive facet joint degeneration (FJD) animal model in rats. FJD was produced by a non-open percutaneous puncture-induced injury on the right lumbar FJs at three consecutive levels. Pressure hyperalgesia in the lower back was assessed by measuring the vocalization response to pressure from a force transducer. After hyperalgesia was established, pathological changes in lumbar FJs and alterations of intervertebral foramen size were assessed by histological and imaging analyses. To investigate treatment options for lumber FJ osteoarthritis-induced pain, animals with established hyperalgesia were administered with analgesic drugs, such as morphine, a selective COX-2 inhibitor, a non-steroidal anti-inflammatory drug (NSAID) (ketorolac), or pregabalin. Effects were assessed by behavioral pain responses. One week after percutaneous puncture-induced injury of the lumbar FJs, ipsilateral primary pressure hyperalgesia developed and was maintained for at least 12 weeks without foraminal stenosis. Animals showed decreased spontaneous activity, but no secondary hyperalgesia in the hind paws. Histopathological and microfocus X-ray computed tomography analyses demonstrated that the percutaneous puncture injury resulted in osteoarthritis-like structural changes in the FJs cartilage and subchondral bone. Pressure hyperalgesia was completely reversed by morphine. The administration of celecoxib produced moderate pain reduction with no statistical significance while the administration of ketorolac and pregabalin produced no analgesic effect on FJ osteoarthritis-induced back pain. Our animal model of non-open percutanous puncture-induced injury of the lumbar FJs in rats shows similar characteristics of low back pain produced by human facet arthropathy.

Expression of cancer stem cell marker during 4-nitroquinoline 1-oxide-induced rat tongue carcinogenesis.

One of the theories regarding oral carcinogenesis is that the tumor growth is initiated from cancer stem cells (CSCs) that self-renew and give rise to differentiated tumor cells, like stem cells do in normal tissues. The most common methods of CSC identification are based on CSC marker expression in carcinogenesis. This study examined the expression of CD133 and CD44, the most commonly used CSC biomarkers in oral squamous cell sarcoma (SCC), with the goal of identifying molecular biomarkers whose expression is associated with the multistep oral carcinogenesis. The expression of CD133, CD44, proliferating cell nuclear antigen (PCNA), and Cytokeratin (CK) was examined by Western blot analysis and confirmed by immunohistochemistry in a 4-nitroquinoline 1-oxide-induced rat tongue carcinogenesis model. Also, the expression of aldehyde dehydrogenase 1 (ALDH1), OCT-4 and Nanog were investigated for alteration of cancer cell stemness by Western blot. Along with the progress of multistep carcinogenesis, there were slight increases of CD133 and CD44 expression in the dysplasia group compared with normal rats. However, CD133 protein level was significantly overexpressed in SCC. The expression of PCNA and CK were low in normal group, but sequentially increased in SCC. ALDH1, Nanog and OCT-4 expression were significantly increased according to SCC grade during carcinogenesis. The findings indicate that CD133 is useful in identifying oral CSCs, which suggests that CD133 may serve as a predictor to identify CSCs with a high risk of oral cancer development.

Radiologic evaluation of degeneration in isthmic and degenerative spondylolisthesis.

STUDY DESIGN: A cross-sectional imaging study. PURPOSE: The objective was to assess the degree of degeneration and the associated factors through imaging studies of the lesion segment and the adjacent superior and inferior segments of isthmic and degenerative spondylolisthesis. OVERVIEW OF LITERATURE: Few articles existed for degeneration and related factors in isthmic and degenerative spondylolisthesis. METHODS: The subjects were 95 patients diagnosed with spondylolisthesis. Simple plain radiographs including flexion and extension and magnetic resonance imaging were used to investigate the degree of translation, disc degeneration, high intensity zone (HIZ) lesion, Schmorl's node (SN) and Modic changes. RESULTS: Advanced disc degeneration, grade 5, was shown to be significant in the index segment of the isthmic type (p=0.034). Overall, type 2 Modic change was most common in both groups and also, it was observed more in the isthmus group, specifically, the index segment compared to the degenerative group (p=0.03). For the SN, compared to the degenerative type, the isthmus type had a significantly high occurrence in the index segment (p=0.04). For the HIZ lesions, the isthmus type had a higher occurrence than the degenerative type, especially in the upper segment (p=0.03). CONCLUSIONS: Most advanced disc degeneration, fifth degree, SN and Modic change occurred more frequently in the lesions of the isthmus type. HIZ lesions were observed more in the isthmus type, especially in the segment superior to the lesion.

Bilateral and simultaneous triceps avulsions in a patient with chronic renal failure receiving long-term peritoneal dialysis.

Simultaneous bilateral triceps tendon avulsions are extremely rare; only 4 cases have been reported in the international literature. This article describes a case of a 32-year-old woman with bilateral and simultaneous avulsions of the triceps tendons. She suffers from chronic renal failure and undergoes peritoneal dialysis every day. The patient presented with ecchymosis and swelling at the posterior aspect of both elbows. While climbing stairs a few hours earlier, she had fallen back on both outstretched arms, experienced moderate pain, and heard a sudden popping sound in her right elbow, followed by similar pain in the left elbow. On examination, she revealed intact extensor mechanism. Radiographs revealed a small osseous flake just proximal to the olecranon in both arms and the absence of associated fractures. During surgery, both triceps tendons appeared normal, other than being avulsed at their tendo-osseous junction. The patient obtained a successful result and full range of motion bilaterally within 3 months postoperatively. A high index of suspicion is needed and careful attention should be paid to elbow pain after minor trauma so that triceps injuries, especially in chronic kidney disease cases, are not missed.

Predictors of failure in medical students.

PURPOSE: This study aimed to identify the predictors of failure in medical students. METHODS: We conducted a 10-year follow-up survey of 231 medical students. The students' general characteristics, study-related factors, health-related behavior, and self-perceived health were examined using questionnaires that were given late in the first year of a premedical course. We evaluated the failure incidence of students using school records from the second year of a premedical course to the fourth year of medical school. The statistical analyses that were used were chi2-test, student t-test, and multiple logistic regression analysis. RESULTS: Sixty-five students experienced failure. Thirty-seven (56.9%) had 1 failure, 11 (16.9%) had 2 failures, 8 (12.3%) had 3 failures, 4 (6.2%) had 4 failures, and 5 (7.7%) had 5 failures. From the results of multiple logistic regression, the rates of failure were significantly higher for those whose grade point average (GPA) in the first year of a premedical course was below 2.5 (Relative Risk [RR]=6.52, 95% Confidence Interval [CI]: 1.42~29.8), who smoked more than 1 pack of cigarettes per day (RR=7.37, 95% CI: 1.23~44.07), who drank more (RR=1.16, 95% CI: 1.02~1.33), and exercised less (RR=0.997, 95% CI: 0.995~0.999). CONCLUSION: It was demonstrated that the incidence of failure in medical students was reflected in their academic records in the first year of a premedical course and by unhealthy lifestyles. This study suggests that students who have poor academic marks and unhealthy lifestyles in the first year of a premedical course should be properly guided to reduce the incidence of failure.

A biomechanical comparison of calf versus cadaver lumbar spine models.

STUDY DESIGN: Biomechanical flexibility tests were performed using calf and human cadaveric lumbar spine models to investigate the effect of anatomic differences. OBJECTIVES: The purpose is to determine if differences exist in biomechanical flexibility testing results between calf and human cadaveric spines when using identical methods and instrumentation. SUMMARY OF BACKGROUND DATA: Calf spines are commonly used in biomechanical research as a substitute for human cadaveric spines in an attempt to reduce expense and specimen variability. Despite widespread use, the validity of this model has not been thoroughly investigated. METHODS: Five fresh calf spines and five human cadaveric spines (L2-L5) were used for nondestructive biomechanical flexibility testing. Maximum moments of 6.4 Nm were achieved in five increments of 1.6 Nm. The rotations of L3 with respect to L4 were measured in 5 cases: 1) intact; 2) following partial discectomy, including partial laminectomy and partial facetectomy; 3) partial discectomy with pedicle screw instrumentation; 4) total discectomy with pedicle screw instrumentation; and 5) pedicle screw instrumentation with interbody graft. Rotational angles were normalized to the intact case to determine the stabilizing effect during each testing case. Data were analyzed using analysis of variance to determine if significant differences existed between the calf spine results and the human cadaveric spine results. RESULTS: In both models, motion increased following discectomy, decreased with instrumentation, and increased with total discectomy. Placement of the interbody graft decreased motion during axial rotation, flexion, and extension but increased lateral bending motion. A two-way analysis of variance revealed no significant differences in the two models during flexion or extension (P > 0.05), but significant differences were discovered in axial rotation and lateral bending (P < 0.05). CONCLUSIONS: Significant differences were identified in flexibility testing between calf and human cadaveric specimens. The calf spine model overestimated the stabilizing effect of instrumentation during lateral bending and underestimated stability during axial rotation. The extrapolation of calf spine data to the in vivo case, especially during axial rotation and lateral bending, should carefully consider the variation between these two models.

The relationship between disc degeneration and morphologic changes in the intervertebral foramen of the cervical spine: a cadaveric MRI and CT study.

A cadaveric study was performed to investigate the relationship between disc degeneration and morphological changes in the intervertebral foramen of cervical spine, including the effect on the nerve root. Seven fresh frozen human cadavers were dissected from C1 to T1, preserving the ligaments, capsules, intervertebral disc and the neural structures. The specimens were scanned with MRI and then scanned through CT scan in the upright position. Direct mid-sagittal and 45 degree oblique images were obtained to measure the dimension of the intervertebral disc height, foraminal height, width, area and segmental angles. Disc degeneration was inversely correlated with disc height. There was a significant correlation between disc degeneration and foraminal width (p<0.005) and foraminal area (p< 0.05), but not with foraminal height. Disc height was correlated with foraminal width but not with height. The segmental angles were decreased more in advanced degenerated discs. There was a correlation between nerve root compression and decreased foraminal width and area (p<0.005). This information and critical dimensions of the intervertebral foramen for nerve root compression should help in the diagnosis of foraminal stenosis of the cervical spine in patients presenting with cervical spondylosis and radiculopathy.

Association of sustained ERK activity with integrin beta3 induction during receptor activator of nuclear factor kappaB ligand (RANKL)-directed osteoclast differentiation.

Osteoclast differentiation is a multi-step process that involves cell proliferation, commitment, and fusion. Some adhesion molecules, including integrin alphavbeta3, have been shown to have roles in osteoclast fusion. In the course of studying with pharmacologic agents known to inhibit protein tyrosine kinases of the Src family, we found that radicicol increased cell fusion during receptor activator of nuclear factor kappaB ligand (RANKL)-driven differentiation of osteoclasts at concentrations far below the ones shown to inhibit its targets in previous studies. Treatments of low doses of radicicol to RAW 264.7 cells that undergo osteoclastic differentiation in the presence of RANKL enhanced the RANKL-induced gene expression of integrin beta3 without any effect on the expression of integrin alphav, which was constitutively high. The cell surface level of integrin alphavbeta3 complexes was consequently augmented by radicicol. In addition, sustained ERK and MEK activation was observed in cells treated with both radicicol and RANKL. More importantly, modulation of ERK activity by the MEK inhibitor U0126 or the gene transduction of a constitutively active form of MEK resulted in a suppression and increment, respectively, of integrin beta3 induction by RANKL. Our data indicate that sustained ERK activity is associated with integrin beta3 induction and subsequent cell surface expression of the alphavbeta3 integrin complex, which may contribute to cell fusion during RANKL-directed osteoclastogenesis.